-----Original Message-----
From: Peter Dodd <[email protected]>
To: [email protected] <[email protected]>
Date: 06 December 2000 16:09
Subject: LF: Re: Coils and amplifiers
Andy said:
Some of us don't have such large antennas as you, Peter. For 1 Watt ERP
I would need approx 4kW RF.
Yes, I am well aware of that - and that is why I mentioned I5TGC's LF
antenna, which must be the smallest of the LF antennas in the LF group.
However, the subject was loading coil cooling - and was it necessary.
I only quoted my transmitter power and antenna current because that
was the only experience I had of using higher power at LF
While on the subject of power amplifiers the only successful design
that I have seen is the one by G3LNP, see 'The LF Experimenter's
Source Book', second edition.
You must have missed MM0ALM signal. He is the strongest on the band and uses
a tube amplifier designed and built by himself. He is several S points
above anyone else. Considering he has no connection with electronics as a
profession he could show most others the way. Seem to remember EI0CF with
his home designed/built amplifier
being the strongest on the band also.
Surprised you missed hearing these two stations. Too many early nights or
day time doozing off !!!!!!!!!!!!!!!!!!!!
G3KEV
I have seen solid state amplifiers that use many separate amplifiers
with the outputs combined using a ferrite transformer. This might be
the way to go in the construction of a less lethal design.
The Decca transmitters were designed with safety (and reliability) in mind.
--
Regards, Peter, G3LDO
<[email protected]>
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